【摘要】 利用FDS数值模拟，研究火源位于支路隧道时，交叉隧道间夹角对主隧道内烟气蔓延的影响，分析了主隧道的烟气浓度、烟气层高度和顶棚最高温度分布状况。结果表明，随着角度由90°减小至30°，主隧道交叉口两侧的烟气浓度呈现非对称特点，钝角方向的烟气浓度大于锐角方向的烟气浓度，但是交叉角度对两个方向的烟气层高度的影响不明显。主隧道内钝角方向顶棚下方烟气最高温度大于锐角方向最高温度，钝角方向最高温度随夹角的减小而增大，锐角方向最高温度随夹角的减小而减小。基于烟气蔓延过程的质量和动量守恒分析，揭示了主隧道内烟气浓度、顶棚最高温度等特征参数的演化机制。更多还原

【Abstract】 The impact of the angle between horizontal crossing tunnels on the fire smoke flow behavior was studied by numerical simulation. The smoke concentration, smoke layer height, and the maximum temperature distribution beneath the ceiling in the main tunnel were analyzed with the fire source in the branch tunnel. The results show that with the decreasing of the angle,the smoke concentrations in the main tunnel at the two sides of the crossing point are asymmetry,and the smoke concentration at the left side(obtuse angle side) is larger than that at the right side(acute angle side). However,the angle has no significant effect on the smoke layer height. The smoke maximum temperature beneath the ceiling at the left side is larger than that at the right side. The maximum temperature at the left side increases with the decreasing of the angle,and the maximum temperature at the right side decreases with the decreasing of the angle. Based on the conservations of mass and momentum of the smoke plume,the evolution mechanisms of the smoke concentration and smoke maximum temperature beneath the ceiling under various angles are revealed.更多还原